1. Field of the Invention
This invention relates to tube fittings and in particular to push-pull type tube fittings arranged for facilitated installation and removal of tube ends.
2. Description of the Prior Art
One improved form of quick-connect type tube fitting is shown in U.S. Pat. No. 3,062,240, of George E. Franck, which patent is owned by the assignee hereof. Therein, a pivotable pawl is provided for locking the tube against axial withdrawal. The pawl carries a biting edge which digs into the tube automatically to prevent such withdrawal. When it is desired to release the tube, however, the pawl is manipulated by means of a knob portion thereof to move the pawl slightly radially outwardly and away from contact with the tube wall surface.
In U.S. Pat. No. 3,291,510, of Joseph D. Kody, which patent is also owned by the assignee hereof, a tube fitting is shown to include an annular springy retainer for effectively positively gripping the tubing and a sealing and gripping ring cooperating with the retainer for sealingly retaining the tube in the fitting. The fitting provides a positive retention of the tube notwithstanding the presence of severe vibrations and high pressure while permitting limited axial and transverse displacement of the tube without loosening of the connection.
Jacob J. Hamburg, in U.S. Pat. No. 3,633,944, discloses a tube coupling of the slip-in type generally similar to that of the Kody patent in providing a sequential arrangement of a spring retainer ring and a resilient sealing ring.
Jacques Sapy et al show in U.S. Pat. No. 3,653,689, a releasable coupling having a clamping member provided with a plurality of flexible jaws. The clamping member has an inclined surface cooperating with a conical surface of a collar to force the jaws inwardly to clamp a tube received in the socket. A packing ring is retained inwardly of the jaws.
In U.S. Pat. No. 3,909,046, of Andre Legris, a connector for fluid conduits is shown which is generally similar to the Sapy et al patent in providing a clamp having pipe-engaging jaws and an inner sealing ring.
In German Pat. No. 005711/75, of Willy Gassert, a fitting is shown having a springy retainer outwardly of means for positioning a plurality of sealing rings.
A number of other tube fittings are known in the prior art. Illustratively, a tube fitting known as the "Sogeclip" tube fitting is shown in a sales leaflet to include a springy retainer radially outwardly of a pair of tubular elements compressing therebetween an O-ring. The springy retainer includes an outer portion extending between the O-ring and body and a variable compression of the O-ring is effected by applying force to the outer tubular element.
In a sales leaflet of Virgo Fluid-Power Corporation, Norton, Massachusetts, a fitting is shown to include a depressible latch locking the latch to the fitting body with the fitting being maintained locked to the tubing at all times.
In the German sales leaflet of Martonair, D1400, a Lynfitting Series 3000 is shown to have a plurality of jaws outwardly of an O-ring for use in connecting a nylon tube to the fitting.